Method and apparatus for making aggregate



July 12, 1966 J. G. CONNELL METHOD AND APPARATUS FOR MAKING AGGREGATE 3 Sheets-Sheet 1 Filed March 9, 1965 INVENTOR.

JOHN G. CONNE LL ATTORNEY METHOD AND APPARATUS FOR MAKING AGGREGATE Filed March 9. 1965 5 Sheets-Sheet 2 F l G. 2

INVENTOR.

JOHN G. CONNELL ATTORNEY y 12, 1966 J. G. CONNELL METHOD AND APPARATUS FOR MAKING AGGREGATE 5 Sheets-Sheet 5 Filed March 9, 1965 INVENTOR. JOHN G. CONNELL BMW ATTORNEYS United States Patent 3,260,513 METHOD AND APPARATUS FOR MAKING AGGREGATE John G. Council, 232 Wyoming Ave, West Pittston, Pa. Filed Mar. 9, 1965, Ser. No. 438,224 Claims. (Cl. 26328) This is a continuation-in-part of application Serial No. 204,448, filed June 22, 1962, now US. Patent No. 3,- 179,391.

This invention relates to improvements in a method and apparatus for making lightweight aggregate such as used in building construction and for insulating materials, and more particularly concerns a method and apparatus for making such aggregate from semi-combustible or noncombustible carbonaceous shale (coal refuse), petro coke, low grade or semi-bituminous coal, or the like.

It is an object of this invention to provide an improved method and apparatus for making aggregate which is more eflicient and satisfactory than those heretofore employed.

It is another object of the invention to provide an improved and efiicient method for producing aggregate from a semi-combustible material (i.e., containing a sufiicient amount of carbon to achieve and sustain combustion) which includes, in a continuous operation, the steps of quickly pre-igniting a pilot layer of the material in an ignition zone, positioning an upper layer of non-ignited material upon the pilot layer :after it has been pre-ignited, and moving both layers together into and through a combustion zone wherein the upper layer of material is ignited from the bottom up by the pre-ignited pilot layer and the entire mass of the material is completely burned.

It is also an object to obtain a low operating cost by utilizing natural or manufactured gas, oil, powdered solid fuel or the like which can be used in a burner nozzle, or an electric are or the like, for producing the desired pro-ignition of the pilot layer of the material.

It is another object of the invention to provide a method which may be employed for producing aggregate from non-combustible materials (which alone have insufficient combustible content to maintain combustion) by blending therewith combustion supporting supplements (in the form of solid or liquid additives).

It is another object of the invention provide improved apparatus for carrying out the present method for making aggregate that is adjustable to efiiciently handle different types and sizes of material.

Other objects and advantages of this invention, including its simplicity and economy, as well as the ease with which it may be adapted to existing equipment, will further become apparent hereinafter and in the drawing in which:

FIG. 1 is a view in vertical longitudinal section of one embodiment of the invention wherein front and rear feed passageways are provided, and the front feed passageway extends to a front opening to an ignition chamber and the rear passageway extends to a rear opening, and a vibrating grate is positioned in the ignition chamber;

FIG. 2 is a view in vertical longitudinal section of another embodiment having front and rear feed passageways extending to the front and rear of an ignition chamber; and

FIG. 3 is a View in vertical longitudinal section of another embodiment wherein front and rear feed passageways are provided and extend to front and rear of an ignition chamber, but without a separate exhaust chamber positioned between the ignition chamber and the front passageway.

Although specific terms are used in the following description for clarity, these terms are intended to refer ice only to the structures shown in the drawings and are not intended to define or limit the scope of the invention.

The embodiment of the invention shown in FIG. 1 includes a storage bin 142 for shale, and a rear feed passageway 143 which extends downwardly from the rear portion of bin 142 and delivers shale to a horizontally disposed, vibrating grate 144 which is preferably water cooled. The shale so delivered forms a pilot layer 145 which, in this embodiment, is moved forwardly by the vibrating grate 144 under the vertically adjustable rear gate 149 and through an ignition chamber 146 located forwardly of the passageway 143, and tumbled from the front end of the grate 144 onto the traveling grate 153. While passing through ignition chamber 146, the pilot layer 145 is subjected to flame 147 which emanates from ignition means such as burners 148.

A drop plate 151 is mounted at the rear of the apparatus and extends from the lower end of the passageway 143 and behind the vibrating grate 144 to a point above and in slightly spaced relation to the traveling grate 153. To aid combustion, free air (indicated by arrows 152) passes downwardly through the vibrating grate 144 and the pilot layer 145 thereon and through the traveling grate 153 into an air chamber 154 (located below the traveling grate) and then upwardly through traveling grate 153 and the pilot layer 145 after it has been dropped thereon from the vibrating grate 144. The free air then passes upwardly through an exhaust chamber 155 and is exhausted through conduit 156.

A front feed passageway 157 directs an upper layer 158 of shale from the front portion of storage bin 142 onto ignited pilot layer 145 as it continues to move forwardly with the traveling grate 153. This front passageway 157 is located forwardly of the exhaust chamber 155 and is defined by rear wall 161 and a leveling gate 162. The shale layers 158 and 145 are transported together by the traveling grate under the leveling gate 162 and into and through a combustion chamber 163 where the entire mass of shale is burned, aided by forced air indicated by the arrows 165 which emanates from air chambers 166 (located below the traveling grate 153) and passes upwardly through the shale in combustion chamber 163.

The embodiment of the invention shown in FIG. 2 includes a storage bin 172 which delivers shale through a rear feed passage 173 directly onto the surface of the top run of a traveling grate 174. A vertically adjustable rear gate 175 determines the height or thickness of the pilot layer 176 which is carried forwardly by traveling grate 174 under the rear gate 175 and through an ignition chamber 177 located immediately ahead of the rear gate. Flame from ignition means such as burners 178 in the ignition chamber pre-ignites the pilot layer 176 as it passes through such chamber.

From the ignition chamber 177 the pre-ignited pilot layer 176 is carried forwardly by the traveling grate through an exhaust chamber 181 wherein forced air, indicated by the arrows 182, passes upwardly through the pilot layer to maintain combustion. The forced air emanates from air chambers 183 .and passes outwardly from exhaust chamber 181 through exhaust conduit 184. As the layer '176 continues moving forwardly with traveling grate 174, an upper layer 185 of non-ignited shale is deposited on top of the pilot layer through front feed passageway 186 from the bin 172, and then both layers 176 and 185 are carried together into and through a combustion chamber 187 where the entire mass of shale is ignited from the bottom up.

The embodiment of the invention shown in FIG. 3 includes a storage bin 201 for the shale or raw aggregate of semi-combustible material. A rear feed passageway 202 feeds the shale through a rear feed surge bin 203 onto the surface of a traveling grate 204. A vertically adjustable rear gate 205 determines the height or thickness of a sealing layer 206 of shale which is carried forwardly by traveling grate 204 through .a rear opening 207 to an ignition chamber 208 which is located immediately ahead of rear gate 205. Flames from ignition means such as burners 211 are directed into ignition chamber 208, and an exhaust conduit 212 is located on each side of the furnace for carrying olf the hot gases generated in the ignition chamber 208 and relieving the pressure generated therein. In this regard, sealing layer 206 plays an important role in sealing rear opening 207 against the escape of hot gases and other material.

A front feed passageway 213 extends downwardly from storage bin 201 to a front opening 214 of exhaust chamber 208 and is defined by ignition chamber leveling gate 215 and front leveling gate 216. Leveling gate 215 is vertically adjustable so as to vary the size of front opening 214, and front leveling gate 216 is vertically adjustable to vary the size of opening 217.

Conduit 212 extends from ignition chamber 208 to an inlet port 221 in combustion chamber 218.

Ignition chamber 208 is completely enclosed by side walls, burner blocks 222 and roof sections 223, 224. Similarly, combustion chamber 218 is completely enclosed by side walls and roof section 225.

Forced air emanates from air chambers 22'6 positioned beneath the top run of traveling grate 204 and passes upwardly through the layers of shale to assist in their burning.

A dribble chamber 227 is also positioned beneath the top run of traveling grate 204. Dribble from sealing layer 206 passes through traveling grate 204 into chamber 227. A screw conveyor 228 is provided to clean out the dribble from chamber 227.

The shale deposited on traveling grate 204 through rear opening 207 forms a sealing layer 206. The shale fed through front feed passageway 213 passes through opening 214 int-o ignition chamber 208 and forms a pilot layer 23 1 which is pre-ignited in ignition chamber 208 by the flame from ignition means such as burners 211 and is then rolled under a non-ignited layer 232 of shale by the action of traveling grate 204 and sealing layer 206 moving forwardly. The three layers pass into combustion chamber 218 through opening 217. All three layers are burned in combustion chamber 218.

In summary, each of the various forms of the apparatus of the present invention for making aggregate from carbonaceous shale or the like comprises an ignition chamber, means for feeding a pilot layer of the material to the ignition chamber, ignition means positioned in the ignition chamber for quickly pre-igniting the pilot layer, means for positioning an upper layer of non-ignited material upon the pilot layer after it has been pre-ignited, a combustion chamber adjacent to the ignition chamber, and -a traveling grate .adapted to receive all layers and carry them together into and through the combustion chamber wherein the entire mass is completely burned.

The lightweight aggregate obtained from this invention is used in making cinder blocks for building construction, among other things.

The present invention may be used not only on carbonaceous shale, but, as pointed out above, may also be used on very low grade shale alone which does not have suflicient carbon to burn. In this case, suflicient combustible material is added to allow pre-i-gnition, and to cause subsequent combustion to occur in the combustion chamber. Accordingly, the invention is not limited to carbonaceous shale but may be used with petro coke, low grade or semi-bituminous coal, and mixtures of non-combustible and combustible materials.

Another advantage of the apparatus of this invention is that it is readily adjustable to suit different kinds of material.

In practice, satisfactory results have been obtained from apparatus wherein the ignition chamber, the combustion chamber and the traveling grate are about 12 feet wide and the burner block assembly includes a series of six burner blocks which cover the full width of the ignition chamber, thereby assuring quick and complete pre-ignition therein of the pilot layer of shale.

The present invention has resulted in considerable savings in initial cost, maintenance, and space, and in the time required to ignite and completely burn the shale. Under the present system, satisfactory results have been obtained by increasing the travel of the grate to feet an hour, with corresponding increase in output.

Carbonaceous shale has a B.t.u. value of perhaps 6000 compared to the B.t.u. value of anthracite coal of from 1200 to 1 400, and so it has not been conventionally used as a fuel because of the difiiculty in igniting it. The present invention provides an inexpensive and easy method of igniting carbonaceous shale, and the 6000 B.t.u.s from the carbonaceous shale may be utilized for various purposes, as, for example, to produce steam in boilers of improved design.

It is to be understood that the form of the invention herewith shown and described is to be taken asa presently preferred embodiment. Various changes may be made in the shape, size and arrangement of parts. Equivalent elements may be substitueed for those illustrated and described herein and certain features of the invention may be utilized independently of the use of other features, all without departing from the spirit or scope of the invention as defined in the subjoined claims.

The claimed invention:

1. Apparatus for making aggregate from carbonaceous shale and the like comprising an ignition chamber, means for feeding material to the ignition chamber and directing at least a substantial portion of the material rearwardly, ignition means in the ignition chamber for directing flame perpendicular to the surface of said rearwardly directed material for pre-igniting a layer of the material to form a pre-igni-ted pilot layer, a forwardly traveling grate arranged and adapted to receive the pre-ignited pilot layer and roll the pilot layer to turn the pilot layer upside down, means for positioning upon the pilot layer after it has been so turned an upper layer of non-ignited material, a combustion chamber adjacent to the ignition chamber and into and through which both layers of the material are adapted to be carried by the traveling grate, the upper layer being adapted to be ignited from the bottom up in the combustion chamber by the pre-ignited pilot layer, and means for sealing said ignition chamber by feeding material into the ignition chamber through a rear opening to form a sealing layer for the ignition chamber to prevent escape of hot gases from the chamber through the rear opening.

2. Apparatus for making aggregate from carbonaceous shale and the like comprising a storage bin containing said shale, a forwardly traveling grate positioned beneath said storage bin, an ignition chamber mounted above the traveling grate and having burner means mounted therein, means for sealing said ignition chamber including a rear feed passageway extending downwardly from the storage bin to a rear opening to the ignition chamber to form a sealing layer of material to prevent escape of hot gases through the rear opening, said traveling grate being arranged and adapted for receiving the shale from the rear feed passageway to form a layer and moving the layer forwardly through the ignition chamber, a front feed passageway extending downwardly from the storage bin to a front opening to the ignition chamber for depositing another layer of shale on the first layer, and a combustion chamber adjacent to the ignition chamber and into and through which both layers of shale are adapted to be carried by the traveling grate.

3. Apparatus for making aggregate from carbonaceous shale and the like comprising a storage bin containing said shale, a forwardly traveling grate positioned beneath said storage bin, an ignition chamber mounted above the traveling grate and having burner means mounted therein, means for sealing said ignition chamber including a rear feed passageway extending downwardly from the storage bin to a rear opening to the ignition chamber to form a sealing layer of material to prevent escape of hot gases through the rear opening, a vibrating grate mounted below the rear feed passageway and above the traveling grate for receiving the shale from the rear feed passageway and moving the shale forwardly beneath the burner means for pre-igniting a layer of the shale to form a pre-ignited pilot layer, an exhaust chamber mounted above the travelirig grate forwardly of the ignition chamber, a front feed passageway extending downwardly from the storage bin to a front opening to the exhaust chamber for depositing on the pre-ignited pilot layer an upper layer of non-ignited shale, and a combustion chamber adjacent to the ignition chamber and into and through which both layers of shale are adapted to be carried by the traveling grate, the upper layer being adapted to be ignited from the bottom up in the combustion chamber by the p-re-ignited pilot layer, said shale entering the rear opening of the ignition chamber acting to seal said opening to prevent escape of hot gases therethrough.

4. Apparatus for making aggregate from carbonaceous shale and the like comprising a storage bin containing a supply of said shale, a forwardly traveling grate positioned beneath said storage bin, an ignition chamber mounted above the traveling grate and having burner means mounted therein, means for sealing said ignition chamber including a rear feed passageway extending downwardly from the storage bin to a rear opening to the ignition chamber to form a sealing layer of material to prevent escape of hot gases through the rear opening, said traveling grate being arranged and adapted for receiving the shale from the rear feed passageway and moving the shale forwardly beneath the burner means for pre-igniting a layer of the shale to form a pre-ignited pilot layer, an exhaust chamber mounted above the traveling grate forwardly of the ignition chamber, a front feed passageway extending downwardly from the storage bin to a front opening to the exhaust chamber for depositing on the p-re-ignited pilot layer an upper layer of non-ignited shale, and a combustion chamber adjacent to the ignition chamber and into and through which both layers of shale are adapted to be carried by the traveling grate, the upper layer being adapted to be ignited from the bottom up in the combustion chamber by the pre-ignited pilot layer, said shale entering the rear opening of the ignition chamber acting to seal said opening to prevent escape of hot gases therethrough.

5. A method for making aggregate from carbonaceous shale and the like in apparatus including an ignition zone with a front and rear opening comprising directing at least a substantial portion of said shale rearwardly into an ignition zone through said front opening to form a pilot layer, a directing flame perpendicular to the surface of said pilot layer in the ignition zone to pre-ignite said pilot layer, rolling the pre-ignited pilot layer to turn the pilot layer upside down, positioning an upper layer of non-ignited material upon the pilot layer after it has been so turned, and directing a portion of said shale into the ignition zone through said rear opening to form a sealing layer for said ignition zone to prevent escape of hot gases from the zone through the rear opening.

References Cited by the Examiner UNITED STATES PATENTS 916,397 3/1909 Dwight 266-21 X 2,380,056 7/1945 Lloyd 266-21 X 2,672,412 3/1954 Bur-row et a1. 263-28 X 3,179,391 4/1965 Connell 263-28 JOHN J. CAMBY, Primary Examiner. 

2. APPARATUS FOR MAKING AGGREGATE FROM CARBONACEOUS SHALE AND THE LIKE COMPRISING A STORAGE BIN CONTAINING SAID SHALE, A FORWARDLY TRAVELING GRATE POSITIONED BENEATH SAID STORAGE BIN, AN IGNITION CHAMBER MOUNTED ABOVE THE TRAVELING GRATE AND HAVING BURNER MEANS MOUNTED THEREIN, MEANS FOR SEALING SAID IGNITION CHAMBER INCLUDING A REAR FEED PASSAGEWAY EXTENDING DOWNWARDLY FROM THE STORAGE BIN TO A REAR OPENING TO THE IGNITION CHAMBER TO FORM A SEALING LAYER OF MATERIAL TO PREVENT ESCAPE OF HOT GASES THROUGH THE REAR OPENING, SAID TRAVELING GRATE BEING ARRANGED AND ADAPTED FOR RECEIVING THE SHALE FROM THE REAR FEED PASSAGEWARY TO FORM A LAYER AND MOVING THE LAYER FORWARDLY THROUGH THE IGNITION CHAMBER, A FRONT FEED PASSAGEWAY EXTENDING DOWNWARDLY FROM THE STORAGE BIN TO 